1. Field of Invention
This invention relates in general to wireless networks and more particularly to providing an out of range indication.
2. Description of Related Art
Recent developments in consumer electronics have included the introduction of wireless personal communication devices such as cell phones, personal walkie-talkies, PDAs (Personal Digital Assistants) and other portable electronic devices. Such devices can be used in many places to wirelessly connect to the Internet, play games, email and other messaging functions as well as provide for personal communications.
Many factors can influence the quality of communications received and/or transmitted to/from a wireless device, including geography, weather, physical obstacles such as foliage and buildings, battery power etc. For example, buildings and other structures can cause interference with the desired communication signals. Such interference typically depends on the method of construction used and the design of the building or other structures and other factors. A user's distance from a transceiver can also result in poor signal quality that can result in unexpected (and annoying) dropped calls, for example.
In order to provide notice of poor signal quality, some wireless devices have a one-way signal strength indicator that is a rough estimator of quality of the radio frequency signal between the covering base station and the receiving wireless device. For example, U.S. Pat. No. 5,809,414 to Coverdale et al. selectively provides to a user a signal strength indication using one or more pre-selected criteria. Unfortunately, however, this signal strength indicator provides the user with an indication of the signal quality only at that particular moment in time which is usually too late to take corrective measures in order to avoid the lost wireless signal or at least mitigate the effects of the lost signal when, or if, it occurs.
Therefore, what is desired is an out of range indication suitable for use in a wireless network.